UI not being updated INotifyPropertyChanged

Question

我有一个绑定到ListBox的类:

class FolderFM : INotifyPropertyChanged
{
    public FolderFM(string path)
    {
        this.Folder = new DirectoryInfo(path);
        this.Name = Folder.Name;
    }
    private string name;
    private DirectoryInfo folder;
    private ObservableCollection<FileInfo> matchingFiles;
    ...
    public ObservableCollection<FileInfo> MatchingFiles 
    {
        get { return matchingFiles; }
        set
        {
            matchingFiles = value;
            FireWhenPropertyChanged("MatchingFiles");
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;
    protected void FireWhenPropertyChanged(string property)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            handler(property, new PropertyChangedEventArgs(property));
        }
    }
}

XAML代码:

<ListBox Name="lstFolders" ItemsSource="{Binding}" Style="{StaticResource FolderBoxStyle}">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <Grid>
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition />
                                <ColumnDefinition Width="25" />
                            </Grid.ColumnDefinitions>
                            <Label Content="{Binding Path=Name}" FontWeight="Bold" FontSize="13" />
                            <Button Content="{Binding Path=MatchingFiles, Converter={StaticResource lcc}}" Grid.Column="1" FontWeight="Bold" Foreground="Red" />
                        </Grid>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>

发生更新的代码后面:

private void btnAnalyze_Click(object sender, RoutedEventArgs e)
    {
        List<FileInfo> remainingFiles = files;
        foreach (FolderFM currentFolder in folders)
        {
            currentFolder.MatchingFiles = new ObservableCollection<FileInfo>();
            string folderName = currentFolder.Folder.Name;
            string[] splitName = folderName.Split(' ');
            for (int i = 0; i < remainingFiles.Count; i++)
            {
                if (remainingFiles[i] == null)
                    continue;
                FileInfo fileName = remainingFiles[i];
                string searchedName = fileName.Name;
                matchScore = 0;
                int searchCount = 0;
                foreach (string part in splitName)
                {
                    if (part.Length < 3 || part == "the")
                        continue;
                    matchScore += searchedName.Contains(part) ? 1 : 0;
                    searchCount += 1;
                }
                if (matchScore == searchCount)
                {
                    string destination = System.IO.Path.Combine(currentFolder.Folder.FullName, fileName.Name);
                    if (File.Exists(destination))
                        continue;
                    Directory.Move(fileName.FullName, destination);
                    currentFolder.MatchingFiles.Add(remainingFiles[i]);
                    //lstFolders.Items.Refresh();
                    remainingFiles[i] = null;
                }
            }
        }
        populateFiles();
    }

附加的Converter接受ObservableCollection并返回它的Count作为字符串。

应用程序正在正常工作，值正在更新，但更改没有反映在UI上。

然而，当我调用:lstFolders.Items.Refresh ();UI得到更新。

我错过/做错了什么??

我看了一些问题，比如:与INotifyPropertyChanged绑定的WPF不更新但我一直没能解决这个问题。

编辑:

DataContext正在被这个方法分配:

private void populateFolders()
    {
        folders = getFolders(selectedFolder.FullName);
        lstFolders.ItemsSource = folders;
    }
private List<FolderFM> getFolders(string path)
    {
        List<FolderFM> d = new List<FolderFM>();
        foreach (string folder in Directory.GetDirectories(path))
        {
            d.Add(new FolderFM(folder));
        }
        return d;
    }

Answer 1

将我的评论转换成答案:

尝试直接绑定到MatchingFiles.Count.

Answer 2

与其创建新的ObservableCollection，不如将其替换为.Clear()。